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Generator labLab
← Generator lab

Part 1 · The idea

  1. 1Split any three
  2. 2Three circuits

Part 2 · Faults in real systems

  1. 3The four faults
  2. 4Grounding
  3. 5Transformers & the line

Part 3 · Protecting the system

  1. 6The fault recorder
  2. 7What relays see
  3. 8Clear it in time

Teacher guide

CTs and relays

CT wiring

Neutral shift reads a voltage transformer (not drawn).

what the relay reads its pickup: drag it. Lit once the bar passes the ring.

Phase currents

The arrows are the three currents the CTs copy to the relays.

Fingerprint dial

Truth table

One row for each fault you try on this visit, newest first.

Which relay lamps each fault lit
FaultPhaseGroundUnbalanceNeutral shift
Numbers
What the CTs and relays measure
QuantitypuOn the lineIn the relay

Each record shows only what a relay recorded. Name the fault type, the phases and whether ground is involved.

Event record

Phase currents
Phase voltages
Use the fingerprint dial

Your answer

Arrow keys or Space pick an answer; Enter checks it.

Fault type
Phases
Ground involved?

Clues: 3I0, or 3V0 with no current, means ground; I2 against I0 points to a pair of faults; the count of high phase currents decides. Your streak stays on this device.

Fault
Faulted phases
Source neutral